Bullock’s Oriole
According to Bruce DiLabio, this is the first time a Bullock’s Oriole has been recorded in the Ottawa region. As Pakenham is a bit of drive, I put off seeing it until Deb became available this morning. We awoke to a thin covering of snow on the ground for the second day in a row, and we wondered what it would mean for both the Mountain Bluebird and the Bullock’s Oriole. The Mountain Bluebird was first on our list, and I was more confident of its survival than the oriole’s – the bluebird is a member of the thrush family, which includes winter-hardy species such as American Robin and Hermit Thrush. Even the Eastern Bluebird is tolerant of our North American winters; although most members of this species normally overwinter in the southern half of the continent, many individuals stay in the northern states and southern Ontario for the winter. Orioles, however, are less tolerant of the cold, and the two Ontario species – Orchard and Baltimore – both spend the winter in Central America, as does the Bullock’s Oriole.
To my surprise, however, the formerly obliging Mountain Bluebird failed to put in an appearance along the fence-line on Century Road. We checked the fence and then did a U-turn and pulled over to scan the tree tops in the area. The bird was a no-show.
We drove from there over to Pakenham, and this time we got lucky. It took us a few minutes to find the favoured apple tree hidden behind a school bus; then we pulled in next to it and watched for a couple of minutes. We had only been there maybe three or four minutes when I spotted a bird fly in. We got our binoculars up – yes, it was the Bullock’s Oriole! The female Bullock’s Oriole can be differentiated from the similar-looking Baltimore Oriole by the white, jagged wingbars (Baltimore Orioles have straight white wingbars) and the bright yellow cheeks (the female Baltimore Oriole has dusky-brown cheeks, and the yellow is brightest on the chest rather than the face). We didn’t want to risk spooking the bird so we stayed in the car and photographed her through the open window. We watched her for maybe three or four minutes before she flew off to the south; she came back after about a minute, though, and resumed feeding on the apples.
Bullock’s Oriole
When she flew off again we decided to leave. We spotted a feeder at the corner and spent some time watching it; to our delight we saw three Pine Siskins feeding with the American Goldfinches and starlings! It’s been a while since I’ve been able to photograph one of these winter finches, so I was quite pleased.
Pine Siskin
From there we decided to head to Andrew Haydon Park to see if the four goose species were still around. Deb still hadn’t seen an adult Greater White-fronted Goose, and I had no objections seeing it again. When we got to the western pond I was dismayed to see that there were no photographers or birders watching the birds on the pond; however, I ran into a birding acquaintance who told me that the “rare” geese were all on the eastern pond. We drove over to the other parking lot, and right away we saw the Greater White-fronted Goose feeding on the northern shore. This photo was taken from the south shore and shows its bright orange legs:
Greater White-fronted Goose
Deb wanted to get closer so we began walking around the pond. To our surprise the Snow Goose was feeding next to the Greater White-fronted Goose, with several Canada Geese on the lawn next to them; fortunately none of them spooked as people went by on the path, so we gave the group a wide berth and joined a small group of photographers on the shore. Although the geese were aware of the attention, they didn’t seem particularly disturbed and continued to feed.
Snow Goose
After photographing the Snow Goose I zoomed out in order to capture three goose species feeding together (click to enlarge). It will likely be a long time before I get these three birds in the same frame again!
Three outta Four ain’t bad! (click to enlarge)
Greater White-fronted Goose (click to enlarge)
The Greater White-fronted Goose made its way toward the water, and eventually something – or someone – disturbed it, for it stretched its neck out and stared at us for a moment before swimming off into the middle of the pond. Here you can see the black bars on its belly and its orange legs peeking out of the water.
Greater White-fronted Goose (click to enlarge)
The Greater White-fronted Goose is named for the white patch of feathers surrounding its bill, although how it can be called “white-fronted” after looking at the Snow Goose standing right beside it is beyond me. Perhaps this is another case where the bird was given its common name after a specimen was examined in the hand, rather than looking at field marks which are actually noticeable in the field or are uniquely different from other species in the same range (both the Ring-necked Duck and Red-bellied Woodpecker come to mind).
Greater White-fronted Goose
Even swimming in the middle of the pond with the large flock of geese Deb and I were pleased with our views of this unique bird. We headed over to the island to get some pictures with the sun at our backs, and I was especially pleased with this one of the goose swimming with a female mallard.
Greater White-fronted Goose
After watching the geese for a while we walked back over to the other pond to check out the gulls standing on the ice. All of them were Ring-billed Gulls; I was disappointed to find no white-winged gulls among them, although I did see a juvenile Herring Gull swimming on the river fairly close to shore.
We scanned the geese next for Cackling Geese and spotted two of them swimming at the back of the pond, their small size noticeable whenever a Canada Goose swam next to them.
Cackling Goose (click to enlarge)
Later, we found at least two more on the eastern pond, although by this time the geese were moving around so much it was difficult to make an accurate count. Still, at least four Cackling Geese were present, making it another four-goose day for me!
Cackling Goose
The solstice is now two days away and winter shows no sign of arriving any time soon. It can stay away as long as it likes, as long as it means more birds like the Bullock’s Oriole, the Greater White-fronted Goose, and the Snow Goose all sticking around!
Author’s Note (March 2016): In early January the temperatures plummeted. On Tuesday, January 5th, the same birder who initially discovered the oriole (Ray Holland) went to check on her to see if she had survived the -15°C overnight low. He found the bird lying in the snow, weak but still alive. The Bullock’s Oriole was taken to the Wild Bird Care Center where she was examined and fed a diet of fruit, crickets and meal-worms in order to regain the 9 grams of weight she had lost. Although she has lost the toenail on one foot due to frost-bite, she is now healthy and will be kept at the WBCC until spring when she can survive on her own.
In the meantime, droppings were collected for DNA analysis in order to confirm the bird’s identity. Preliminary analysis showed that the mitochondrial DNA contained the genes of a Baltimore Oriole – the expected species in eastern Ontario. Mitochondrial DNA is passed down through the maternal line, indicating that one of its female ancestors was a Baltimore Oriole. In other words, the Bullock’s Oriole is not a pure Bullock’s Oriole, although the DNA obtained cannot determine how far back in its ancestry the hybridization occurred. This led to a news article being published on the CBC website about how birders were fooled by the imposter.
Debate about whether this bird was countable as a Bullock’s Oriole ensued. The plumage clearly pointed to a female Bullock’s Oriole, and plumage is how birders chiefly identify birds in the field. This was a case of whether identification is best made by phenotype (the physical appearance expressed by an organism’s genes) vs. genotype (the set of genes that makes up an organism). Well-known local birdwatcher Bruce DiLabio weighed in, claiming that birders identify birds by their plumage, not their DNA, and that as far as he could tell, the bird is a Bullock’s Oriole.
Then, on February 9th, Jeff Skevington released the results of the nuclear DNA testing that was subsequently done. Unlike mitochondrial DNA, one-half of the nuclear DNA is received from the mother, and one-half is received from the father. Nuclear DNA is what is passed down to the offspring of a male and female during conception and, in humans, is the reason why a child might inherit its mother’s auburn hair and its father’s large nose. The nuclear DNA of Ottawa’s celebrity oriole confirmed that both parents were, in fact, Bullock’s Orioles, which is why it looks like a Bullock’s Oriole and not a Baltimore Oriole. However, it should be noted that only one gene could be tested, and that only a few sequences from this gene are available in public databases for comparison. The gene tested has only 4 nucleotide base pairs (out of hundreds, if not thousands) which are consistently different between the two species – an absolutely minuscule number on which to confirm the bird’s identity!
Further, the fact that its mitochondrial DNA contained the genes of a Baltimore Oriole indicates that this bird likely came from the extremely narrow hybridization zone that runs south from Alberta through Kansas. There are far fewer hybrids living than there are pure Bullock’s Orioles, which means that the probability of such a hybrid making its way to Ottawa is much smaller than the minute chance of a pure Bullock’s Oriole finding its way here – all of which goes to say that this bird truly is a fascinating mega-rarity with a very intriguing lineage.
Author’s Further Note (November 2016): Further DNA testing has now confirmed that both parents of this bird were indeed Bullock’s Orioles. So while this bird has a Baltimore Oriole somewhere in its ancestry, it is not a hybrid, which is defined biologically as the offspring resulting from the cross between parents of different species or sub-species. Both parents were Bullock’s Orioles, making this individual a Bullock’s Oriole as well. The last I heard of this bird, it spent the summer at the Wild Bird Care Center as it had not completed its molt and they felt they could not release it. I am not sure if they were able to release it in time to join the local Baltimore Orioles migrating south, or if they ended up keeping it there for another winter.
The Pathless Wood 
Here’s another one from Gillian. She’s very prolific!
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